The present invention relates to a thermal printing apparatus for printing information such as images and letters to a recording medium such as a card, and a thermal transfer film for the thermal printing apparatus. More particularly, the present invention relates to a thermal printing apparatus capable of re-writing information such as letters or numbers with a thermo-reversible printing method, and a thermal transfer film for the thermal printing apparatus.
Conventionally, when a card-shaped recording medium such as a credit card, cash card, license card, and ID card is produced, a thermal transfer type printing apparatus is used for thermally transferring a desired image and letter to a recording medium via a thermal transfer film with a thermal transfer head. Such a printing apparatus with the thermal transfer method is disclosed in Japanese Patent No. 3330355. In the thermal transfer method, a thermal sublimate ink is used because of superior color tones and high quality images. Therefore, the thermal transfer method is effective for printing a photograph.
Recently, an over-write card or rewritable card has been used as a point card, prepaid card, or leisure card in which data such as a number or letter can be repeatedly printed and written. A printing apparatus (reader/writer) capable of re-writing data with a thermo-reversible printing method has been disclosed in Japanese Patent No. 3125247.
There has been a credit card (for example IC cards) having a rewritable display data region in the market (for example, a fine rewrite IC card manufactured by TOPPAN FORMS Co., Ltd.). In such a card, dyes and a developing agent are formed in layers in the display data region for providing color. For example, Japanese Patent Publication (Kokai) No. 08-224973 has disclosed a card with a face and individual information such as a name of an owner. Also, numbers are printed in a rewritable display data region on the card.
In a printing apparatus with the thermal transfer method mentioned above, a plastic film such as a polyester film is used as a base sheet for a thermal transfer film for printing an image or letter. According to an application, the thermal transfer film includes a sublimate type thermal transfer film in which a dye layer formed of a thermal sublimate dye and a binder such as a resin is formed on a surface of a base sheet, and a thermal transfer film in which an ink layer formed of a coloring agent such as paint and a hot-melt compound is formed instead of the dye layer. A heating device such as a thermal head applies thermal energy corresponding to an image from a backside of the thermal transfer film, so that an ink component is sublimated or melt. Accordingly, the ink component is transferred to a medium such as a card or plastic sheet, thereby forming an ink image of a letter or an image.
When personal information of an owner is printed, and a letter or an image is printed in the display data region on the card, it is necessary to provide a printing apparatus for printing the individual information of the owner and another printing apparatus for printing the image in the display data region, thereby increasing a set up space, cost, and an amount of work, and lowering productivity. If a printing apparatus with a single configuration can print, it is possible to reduce a space and cost while improving productivity.
In a printing apparatus with a thermo-reversible printing method for repeatedly printing and re-writing display data such as numbers and letters, a dye and a developing agent are formed in layers on a card medium for providing color. A heating device such as a thermal head applies thermal energy to the card medium to form display data such as numbers and letters. Accordingly, it is not necessary to use the thermal transfer film described above.
In view of the situation described above, an object of the present invention is to provide a thermal transfer printing apparatus capable of reducing an installation space and cost and improving convenience for an operator for issuing a card medium.
Another object of the present invention is to provide a thermal transfer film for a printing apparatus for irreversibly printing individual information of a card owner and reversibly printing in a display data region on a card medium, thereby performing an appropriate printing process.
Further objects and advantages of the invention will be apparent from the following description of the invention.